This section provides background information related to the present disclosure which is not necessarily prior art.
To authenticate a user, many websites employ images of distorted text which a user needs to decipher in order to correctly input the text shown in the image, for example the CAPTCHA™ system. Upon entering the correct text, i.e. the text shown in the image, the user is authenticated. These images are supposed to be unintelligible for a computer and thus only a human should be capable of deciphering these texts. Therefore, only humans should be able to be authenticated as users. The ongoing improvement of optical character recognition (OCR) technology however requires these text images to be more and more distorted since continuously improving OCR technologies enable computers to decipher these distorted text images. In order to continue to use this approach, text images need to be more and more distorted to be too difficult to decipher for OCR technologies. Yet, increased distortion not only renders these text images harder to decipher for OCR technologies but also for humans, making this approach to user authentication more and more cumbersome for human users.